A scullery is like a special room in a house where people wash dishes and do other cleaning work. It's sort of like a kitchen but just for cleaning and doing chores!
In bigger old houses, they'd have a scullery where people would go when they finished eating to wash all the dishes and clean everything up. They would also clean other important things like pots, pans, and silverware. It’s kind of like when you finish playing with toys and have to put them away and clean up the mess you made. The scullery was a place where everything could be tidied up so the kitchen can be ready for the next meal.
The people who worked in the scullery would work very hard, scrubbing everything clean and making sure everything was nice and shiny. They might also have to do other lots of chores like fetching water, cleaning clothes, or polishing things.
All in all, a scullery is an important part of any old house because it helps keep everything clean and tidy, just like when you clean up your toys when you finish playing.